The National 9/11 Memorial & Museum is a memorial and museum located in New York City, United States, commemorating the September 11 attacks of 2001, which killed nearly 3,000 people. The memorial and museum are located at the World Trade Center site in lower Manhattan, where the Twin Towers of the World Trade Center once stood.

The memorial consists of two large reflecting pools that are located on the exact footprints of the original Twin Towers. These pools are surrounded by bronze panels inscribed with the names of the victims of the attacks. The pools are constantly refilled with cascading water, and are lit at night.

The museum, which opened in 2014, contains artifacts, photographs, and video footage related to the attacks. It is located underground, beneath the memorial plaza. Exhibits include pieces of the original towers, personal belongings of victims and first responders, and recordings of phone calls and radio transmissions from the day of the attacks.

Visitors to the memorial and museum can also participate in guided tours, which provide additional context and insight into the events of September 11th. The museum and memorial are open to the public and admission is available with timed tickets.